Responses of the phytoplankton to a deliberate attempt to raise the trophic status of an acidic, oligotrophic mountain lake

The paper reports the impact of a sharp artificial enrichment of the available phosphorus in a small, acidic and oligotrophic corrie lake and its effects upon the phytoplankton supported. Annual average chlorophyl- l increased tenfold within two years, from [sim ] 1.2 to 12.6 µg chl a 1-1, but the species represented by large populations are the same as previously. Chrysophyte species, however, make up a smaller fraction of the total crop.